Thymine
- Formula: C5H6N2O2
- Molecular weight: 126.1133
- IUPAC Standard InChIKey: RWQNBRDOKXIBIV-UHFFFAOYSA-N
- CAS Registry Number: 65-71-4
- Chemical structure:
This structure is also available as a 2d Mol file - Other names: 2,4(1H,3H)-Pyrimidinedione, 5-methyl-; Thymin; 2,4-Dihydroxy-5-methylpyrimidine; 5-Methyluracil; 5-Methyl-2,4-dioxypyrimidine; 5-Methyl-2,4(1H,3H)-pyrimidinedione
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Condensed phase thermochemistry data
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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔfH°liquid | -462.80 ± 0.84 | kJ/mol | Ccr | Nabavian, Sabbah, et al., 1977 | ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔcH°liquid | -2362.23 ± 0.84 | kJ/mol | Ccr | Nabavian, Sabbah, et al., 1977 | ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔcH°solid | -2369. | kJ/mol | Ccb | Fischer and Wrede, 1904 | Heat of combustion corrected for pressure; ALS |
| ΔcH°solid | -2367.3 | kJ/mol | Ccb | Lemoult, 1904 | ALS |
Constant pressure heat capacity of solid
| Cp,solid (J/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 150.2 | 298. | Kilday, 1978 | DH |
| 151.4 | 298.15 | Alvarez and Biltonen, 1973 | DH |
Phase change data
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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos
DH - Eugene S. Domalski and Elizabeth D. Hearing
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| Tfus | 321.3 | K | N/A | Eykman, 1889 | Uncertainty assigned by TRC = 1. K; TRC |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔvapH° | 134.1 ± 4.2 | kJ/mol | V | Nabavian, Sabbah, et al., 1977 | ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔsubH° | 131.3 ± 4.0 | kJ/mol | N/A | Burkinshaw and Mortimer, 1984 | AC |
| ΔsubH° | 138. ± 10. | kJ/mol | TE | Ferro, Bencivenni, et al., 1980 | AC |
| ΔsubH° | 134.1 ± 4.2 | kJ/mol | C | Nabavian, Sabbah, et al., 1977, 2 | AC |
Enthalpy of sublimation
| ΔsubH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 125.7 ± 3.6 | 411. | ME | Burkinshaw and Mortimer, 1984 | Based on data from 383. to 438. K.; AC |
| 124.4 ± 1.3 | 403. | QR | Teplitsky, Yanson, et al., 1980 | Based on data from 378. to 428. K.; AC |
Enthalpy of fusion
| ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 17.51 | 321.3 | Domalski and Hearing, 1996 | AC |
| 17.510 | 321.3 | Eykman, 1889, 2 | DH |
Reaction thermochemistry data
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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled as indicated in comments:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
RCD - Robert C. Dunbar
Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.
Individual Reactions
By formula: C5H7N2O2+ + C5H6N2O2 = (C5H7N2O2+ • C5H6N2O2)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 126. | kJ/mol | PHPMS | Meot-Ner (Mautner), 1979 | gas phase; M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrS° | 150. | J/mol*K | PHPMS | Meot-Ner (Mautner), 1979 | gas phase; M |
By formula: Na+ + C5H6N2O2 = (Na+ • C5H6N2O2)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 135. ± 4. | kJ/mol | CIDT | Rodgers and Armentrout, 2000 | RCD |
| ΔrH° | 144. | kJ/mol | CIDC | Cerda and Wesdemiotis, 1996 | RCD |
By formula: K+ + C5H6N2O2 = (K+ • C5H6N2O2)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 102. | kJ/mol | CIDC | Cerda and Wesdemiotis, 1996 | RCD |
Ion clustering data
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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled as indicated in comments:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
RCD - Robert C. Dunbar
Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.
Clustering reactions
By formula: C5H7N2O2+ + C5H6N2O2 = (C5H7N2O2+ • C5H6N2O2)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 126. | kJ/mol | PHPMS | Meot-Ner (Mautner), 1979 | gas phase; M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrS° | 150. | J/mol*K | PHPMS | Meot-Ner (Mautner), 1979 | gas phase; M |
By formula: K+ + C5H6N2O2 = (K+ • C5H6N2O2)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 102. | kJ/mol | CIDC | Cerda and Wesdemiotis, 1996 | RCD |
By formula: Na+ + C5H6N2O2 = (Na+ • C5H6N2O2)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 135. ± 4. | kJ/mol | CIDT | Rodgers and Armentrout, 2000 | RCD |
| ΔrH° | 144. | kJ/mol | CIDC | Cerda and Wesdemiotis, 1996 | RCD |
IR Spectrum
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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled by: Coblentz Society, Inc.
Condensed Phase Spectrum
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Notice: Except where noted, spectra from this collection were measured on dispersive instruments, often in carefully selected solvents, and hence may differ in detail from measurements on FTIR instruments or in other chemical environments. More information on the manner in which spectra in this collection were collected can be found here.
Notice: Concentration information is not available for this spectrum and, therefore, molar absorptivity values cannot be derived.
Additional Data
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| Owner | Copyright (C) 1987 by the Coblentz Society Collection (C) 2018 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
|---|---|
| Origin | K. K. DEB-NCI FREDERICK CANCER RESEARCH CENTER |
| Source reference | COBLENTZ NO. 9740 |
| Date | 1974/08/20 |
| Name(s) | 5-methyl-2,4(1H,3H)-pyrimidinedione 5-methyluracil |
| State | SOLID (1.8 mg / 500 mg KBr DISC) |
| Instrument | PERKIN-ELMER 180 (GRATING) |
| Instrument parameters | GRATINGS: 2000, 1000, 500, 250 CM-1; FILTER CHANGE: 2970, 2000, 1485, 1000, 743, 500, 372, 250, 186 CM-1. |
| Resolution | 2 |
| Sampling procedure | TRANSMISSION |
| Data processing | DIGITIZED BY COBLENTZ SOCIETY (BATCH II) FROM HARD COPY |
UV/Visible spectrum
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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Spectrum
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Additional Data
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| Source | Wilson, 1948 |
|---|---|
| Owner | INEP CP RAS, NIST OSRD Collection (C) 2007 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
| Origin | INSTITUTE OF ENERGY PROBLEMS OF CHEMICAL PHYSICS, RAS |
| Source reference | RAS UV No. 11048 |
| Instrument | n.i.g. |
| Melting point | 316 |
References
Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Ion clustering data, IR Spectrum, UV/Visible spectrum, NIST Subscription Links, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Nabavian, Sabbah, et al., 1977
Nabavian, P.M.; Sabbah, R.; Chastel, R.; Laffitte, M.,
Thermodynamique de composes azotes. II. Etude thermochimique des acides aminobenzoiques, de la pyrimidine, de l'uracile et de la thymine.,
J. Chim. Phys., 1977, 74, 115-126. [all data]
Fischer and Wrede, 1904
Fischer, E.; Wrede, F.,
Uber die Verbrennungswarme einiger organischer Verbindungen,
Sitzungsber. Dtsch. Akad. Wiss. Berlin Kl. Math. Phys. Tech., 1904, 687-715. [all data]
Lemoult, 1904
Lemoult, M.P.,
Remarques sur une serie recenie de determinations calorimetriques,
Compt. Rend., 1904, 663-635. [all data]
Kilday, 1978
Kilday, M.V.,
Enthalpies of solution of the nucleic acid bases. 2. Thymine in water,
J. Res., 1978, NBS 83, 529-537. [all data]
Alvarez and Biltonen, 1973
Alvarez, J.; Biltonen, R.,
Nucleic acid-solvent interactions: temperature dependence of the heat of solution of thymine in water and ethanol,
Biopolymers, 1973, 12, 1815-1828. [all data]
Eykman, 1889
Eykman, J.F.,
Z. Phys. Chem., Stoechiom. Verwandtschaftsl., 1889, 4, 497. [all data]
Burkinshaw and Mortimer, 1984
Burkinshaw, Philip M.; Mortimer, Colin T.,
Enthalpies of sublimation of transition metal complexes,
J. Chem. Soc., Dalton Trans., 1984, 1, 75, https://doi.org/10.1039/dt9840000075
. [all data]
Ferro, Bencivenni, et al., 1980
Ferro, D.; Bencivenni, L.; Teghil, R.; Mastromarino, R.,
Vapour pressures and sublimation enthalpies of thymine and cytosine,
Thermochimica Acta, 1980, 42, 1, 75-83, https://doi.org/10.1016/0040-6031(80)87117-6
. [all data]
Nabavian, Sabbah, et al., 1977, 2
Nabavian, M.; Sabbah, R.; Chastel, R.; Laffitte, M.,
J. Chim. Phys.Phys.-Chim. Biol., 1977, 74, 115. [all data]
Teplitsky, Yanson, et al., 1980
Teplitsky, A.B.; Yanson, I.K.; Glukhova, O.T.; Zielenkiwicz, A.; Zielenkiewicz, W.; Wierzchowski, K.L.,
Thermochemistry of aqueous solutions of alkylated nucleic acid bases,
Biophysical Chemistry, 1980, 11, 1, 17-21, https://doi.org/10.1016/0301-4622(80)85003-4
. [all data]
Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D.,
Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III,
J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985
. [all data]
Eykman, 1889, 2
Eykman, J.F.,
Zur kryoskopischen Molekulargewichtsbestimmung,
Z. Physik. Chem., 1889, 4, 497-519. [all data]
Meot-Ner (Mautner), 1979
Meot-Ner (Mautner), M.,
Ion Thermochemistry of Low Volatility Compounds in the Gas Phase. II. Intrinsic Basicities and Hydrogen Bonded Dimers of Nitrogen Heterocyclics and Nucleic Bases,
J. Am. Chem. Soc., 1979, 101, 9, 2396, https://doi.org/10.1021/ja00503a027
. [all data]
Rodgers and Armentrout, 2000
Rodgers, M.T.; Armentrout, P.B.,
Noncovalent Interactions of Nucleic Acid Bases (Uracil, Thymine, and Adenine) with Alkali Metal Ions. Threshold Collision-Induced Dissociation and Theoretical Studies,
J. Am. Chem. Soc., 2000, 121, 35, 8548, https://doi.org/10.1021/ja001638d
. [all data]
Cerda and Wesdemiotis, 1996
Cerda, B.A.; Wesdemiotis, C.,
PAs of Peptides,
J. Am. Chem. Soc., 1996, 118, 11884. [all data]
Wilson, 1948
Wilson, W.,
J. Chem. Soc., 1948, 1157. [all data]
Notes
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- Symbols used in this document:
Cp,solid Constant pressure heat capacity of solid Tfus Fusion (melting) point ΔcH°liquid Enthalpy of combustion of liquid at standard conditions ΔcH°solid Enthalpy of combustion of solid at standard conditions ΔfH°liquid Enthalpy of formation of liquid at standard conditions ΔfusH Enthalpy of fusion ΔrH° Enthalpy of reaction at standard conditions ΔrS° Entropy of reaction at standard conditions ΔsubH Enthalpy of sublimation ΔsubH° Enthalpy of sublimation at standard conditions ΔvapH° Enthalpy of vaporization at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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